title: Persistence of antibodies in adolescents 18-24 months after immunization with one, two, or three doses of 4CMenB meningococcal serogroup B vaccine.
abstract: We previously demonstrated the immunogenicity and tolerability of the serogroup B meningococcal vaccine, 4CMenB (Bexsero), in 11-17 y-olds randomized to receive 1, 2, or 3 doses at 1, 2, or 6 mo intervals. Participants in this extension study provided an additional blood sample 18-24 mo after last vaccine dose, to assess persistence of serum bactericidal activity with human complement (hSBA), and to compare with age-matched 4CMenB-naïve controls. In the original study, one month after one 4CMenB dose, 93% of subjects had seroprotective hSBA titers (≥4) against indicator serogroup B strains for individual vaccine antigens (fHbp, NadA and NZOMV), increasing to ~100% after two or three doses. After 18-24 mo, 62-73% of subjects given one dose had titers ≥4 against the three antigens, significantly lower rates than after two (77-94%) or three (86-97%) doses. Only proportions with titers ≥ 4 against NZOMV were significantly different between the two (77%) and three (90%, p < 0.0001) dose groups. These results confirm that two doses of 4CMenB, administered 1 to 6 mo apart, provide good levels of bactericidal activity against serogroup B meningococci, which were sustained at least 18-24 mo in over 64% of adolescents for all three tested vaccine-related antigens.
authors.affiliation: Departamento de Pediatría; Hospital Dr Luis Calvo Mackena; Facultad de Medicina; Universidad de Chile; Santiago, Chile.
authors.forename: Maria Elena
authors.initials: ME
authors.lastname: Santolaya
authors.forename: Miguel
authors.initials: M
authors.lastname: O'Ryan
authors.forename: María Teresa
authors.initials: MT
authors.lastname: Valenzuela
authors.forename: Valeria
authors.initials: V
authors.lastname: Prado
authors.forename: Rodrigo F
authors.initials: RF
authors.lastname: Vergara
authors.forename: Alma
authors.initials: A
authors.lastname: Muñoz
authors.forename: Daniela
authors.initials: D
authors.lastname: Toneatto
authors.forename: Gabriela
authors.initials: G
authors.lastname: Graña
authors.forename: Huajun
authors.initials: H
authors.lastname: Wang
authors.forename: Peter M
authors.initials: PM
authors.lastname: Dull
mesh_terms: D000293:Adolescent; D000907:Antibodies, Bacterial / Q000097:blood*; D001770:Blood Bactericidal Activity; D002648:Child; D003165:Complement System Proteins / Q000276:immunology; D005260:Female; D006801:Humans; D008297:Male; D022401:Meningococcal Vaccines / Q000008:administration & dosage* / Q000276:immunology*; D009345:Neisseria meningitidis / Q000276:immunology*; D055815:Young Adult
chemical_list: C570015:4CMenB vaccine; D000907:Antibodies, Bacterial; D022401:Meningococcal Vaccines; D003165:Complement System Proteins
keywords: adolescents; antibodies; meningococcal; persistence; serogroup B; vaccine